At the initial charge both wrestlers must jump up from the crouch simultaneously after touching the surface of the ring with two fists at the start of the bout, and the referee can restart the bout if this simultaneous touch does not occur. Upon completion of the bout, the referee must immediately designate his decision by pointing his gunbai or war-fan towards the winning side.
In contrast to the time in bout preparation, bouts are typically very short, usually less than a minute, and often only a few seconds. Extremely rarely a bout can go on for many minutes (up to four minutes), in which case the referee or one of the judges sitting around the ring may call a mizu-iri or "water break". The wrestlers are carefully separated, have a brief break and then return to the exact position they left off in. It is the referee's responsibility to reposition the wrestlers. If after four more minutes they are still deadlocked they may have a second break, after which they start from the very beginning. Further deadlock with no end of the bout in sight can lead to a draw (hikiwake), an extremely rare result in modern sumo. The last draw in the top division was in September 1974.